不同时效制度对Al-0．42Mg-0．50Si-0．99Cu合金力学性能和晶间腐蚀性能的影响  

Effect of Different Aging Treatmrnts on Mechanical Properties and Intergranular Corrosion Properties of Al-0.42Mg-0.50Si-0.99Cu Alloy

作　　者：尹德艳[1,2] 杨伏良[1,3] 黄珂[1,3] 马凯[1,3] 

机构地区：[1]中南大学材料科学与工程学院,长沙410100 [2]长沙新振升集团有限公司,长沙410100 [3]中南大学有色金属材料科学与工程教育部重点实验室,长沙410083

出　　处：《机械工程材料》2013年第5期36-40,45,共6页Materials For Mechanical Engineering

基　　金：国家“863”高新技术研究资助项目(2003AA332070);长沙市科技成果产业化资金专项资助项目(K0902002-11)

摘　　要：设计了一种成分为Al-0.42Mg-0.50Si-0.99Cu的新型工业型材用铝合金,通过光学显微镜、透射电镜及万能拉伸试验机等研究了不同时效制度对其组织、力学性能以及晶间腐蚀性能的影响。结果表明:合金在T6欠时效时晶界无明显析出相;T6峰时效时晶界析出物细小连续分布,晶间腐蚀严重;随时效时间延长,Q′相增多并逐渐粗化,晶界析出物粗大呈非连续分布;双级时效时晶内析出了大量Q′相,晶界析出相球化且析出相之间的间距增大,呈断续分布,无析出带(PFZ)变宽,抗腐蚀能力增强;合金在T6峰时效时强度最高,但晶间腐蚀敏感性大;双级时效可在强度损失不大的情况下明显提高其耐蚀性。A new type of AbMg-Si-Cu aluminum alloy was designed, and the alloy composition was A1-0. 42Mg-0. 50Si-0. 99Cu. The effects of different aging treatments on microstructure, mechanical properties and corrosion behavior were studied by optical microscopy, transmission electron microscopy and means of conventional tensile test. The results show that no distinct grain boundary precipitates were observed in T6 under-aging state and the grain boundary precipitates are small and continuously distributed in T6 peak-aging state, and intergranular corrosion was serious. With the increase of aging time, Q＇ phase increased and coarsened, the grain boundary precipitates were coarsened obviously and sparsely distributed. In double aging state, there are plenty of Qr precipitates in matrix, grain boundaries precipitates were spheroidization, the spacing between precipitated phases increased, precipitated phaseand were continuously distributed and the PFZ was broaden. In T6 peak-aging state, the alloy had the most serious intergranular corrosion tendency and had the highest strength, however, the corrosion resistance was obviously improved while tensile strength was a little decrease in double aging state.

关 键 词：铝镁硅铜合金 力学性能 晶间腐蚀 微观组织 

分 类 号：TG164.2[金属学及工艺—热处理]